Meander flow takes place in one single channel which oscillates more or less regularly with amplitudes that tend to increase with time.Meanders are found in beds of fine sediments with gentle slopes.In this study,effo...Meander flow takes place in one single channel which oscillates more or less regularly with amplitudes that tend to increase with time.Meanders are found in beds of fine sediments with gentle slopes.In this study,effort will be made to investigate meanders’turbulent boundary layer and to improve the present knowledge about the river meandering phenomena.It is assumed that the development of the perturbations which develop into meanders or braids,is longer than the width of the channel.Interaction between the flow and mobile boundaries produces channel patterns which are classified as meandering or braided.It is therefore long compared with the ripples or dunes which cover the bed of such a channel and whose wavelength is shorter than the width of the channel.The variation of resistance to flow and rate of transport of bed material with velocity are discussed briefly and taken into account.Meander flow and meander shear stress distribution of the channel are described.The basis is a steady,two-dimensional model of flow in an alluvial channel with variable curvature.The meander development is described by forcing a travelling,small-amplitude channel alignment wave on the system,and determining the growth characteristics of the wave.Laboratory data are used to verify the formulas.展开更多
In Cloud computing, data and service requests are responded by remote processes calls on huge data server clusters that are not totally trusted. The new computing pattern may cause many potential security threats. Thi...In Cloud computing, data and service requests are responded by remote processes calls on huge data server clusters that are not totally trusted. The new computing pattern may cause many potential security threats. This paper explores how to ensure the integrity and correctness of data storage in cloud computing with user＇s key pair. In this paper, we aim mainly at constructing of a quick data chunk verifying scheme to maintain data in data center by implementing a balance strategy of cloud computing costs, removing the heavy computing load of clients, and applying an automatic data integrity maintenance method. In our scheme, third party auditor （TPA） is kept in the scheme, for the sake of the client, to periodically check the integrity of data blocks stored in data center. Our scheme supports quick public data integrity verification and chunk redundancy strategy. Compared with the existing scheme, it takes the advantage of ocean data support and high performance.展开更多
文摘Meander flow takes place in one single channel which oscillates more or less regularly with amplitudes that tend to increase with time.Meanders are found in beds of fine sediments with gentle slopes.In this study,effort will be made to investigate meanders’turbulent boundary layer and to improve the present knowledge about the river meandering phenomena.It is assumed that the development of the perturbations which develop into meanders or braids,is longer than the width of the channel.Interaction between the flow and mobile boundaries produces channel patterns which are classified as meandering or braided.It is therefore long compared with the ripples or dunes which cover the bed of such a channel and whose wavelength is shorter than the width of the channel.The variation of resistance to flow and rate of transport of bed material with velocity are discussed briefly and taken into account.Meander flow and meander shear stress distribution of the channel are described.The basis is a steady,two-dimensional model of flow in an alluvial channel with variable curvature.The meander development is described by forcing a travelling,small-amplitude channel alignment wave on the system,and determining the growth characteristics of the wave.Laboratory data are used to verify the formulas.
基金Supported by the National Natural Science Foundation of China (60633020, 60573036)the Fundamental Funding Research Project of the Engineering College of APF (WJY 201026)
文摘In Cloud computing, data and service requests are responded by remote processes calls on huge data server clusters that are not totally trusted. The new computing pattern may cause many potential security threats. This paper explores how to ensure the integrity and correctness of data storage in cloud computing with user＇s key pair. In this paper, we aim mainly at constructing of a quick data chunk verifying scheme to maintain data in data center by implementing a balance strategy of cloud computing costs, removing the heavy computing load of clients, and applying an automatic data integrity maintenance method. In our scheme, third party auditor （TPA） is kept in the scheme, for the sake of the client, to periodically check the integrity of data blocks stored in data center. Our scheme supports quick public data integrity verification and chunk redundancy strategy. Compared with the existing scheme, it takes the advantage of ocean data support and high performance.
